EP 0577783 A4 19940413 -
Publication
Application
Priority
- US 82137992 A 19920116
- US 9209016 W 19921026
Abstract (en)
[origin: US5186612A] In the present fluid system, a variable pressure inlet system is provided and operational to control the operating pressure level of a charge pump in response to various operating parameters of the fluid system. The charge pump provides pressurized fluid to an inlet of a hydraulic pump to insure filling of the pumping chambers therein. By having the operating pressure level of a variable pressure relief valve that is connected to the charge pump controlled between a minimum pressure level and a maximum pressure level responsive to various operating perimeters of the system, the degree of horsepower needed to drive the charge pump is controlled. The operating pressure level of the variable pressure relief valve may be controlled in response to movement of a swash plate of the hydraulic pump, the speed of the input drive mechanism to the hydraulic pump, the movement of the spool of the control valve, or by the operating pressure level representative of a load L or by any combinations thereof acting in parallel one with the other.
IPC 1-7
IPC 8 full level
F04B 23/04 (2006.01); F04B 49/00 (2006.01); F04B 49/08 (2006.01)
CPC (source: EP US)
F04B 49/007 (2013.01 - EP US); F04B 49/08 (2013.01 - EP US)
Citation (search report)
- No further relevant documents disclosed
- See references of WO 9314317A1
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
US 5186612 A 19930216; CA 2099666 A1 19930717; DE 69218765 D1 19970507; DE 69218765 T2 19971113; EP 0577783 A1 19940112; EP 0577783 A4 19940413; EP 0577783 B1 19970402; JP H06506521 A 19940721; WO 9314317 A1 19930722
DOCDB simple family (application)
US 82137992 A 19920116; CA 2099666 A 19921026; DE 69218765 T 19921026; EP 92922643 A 19921026; JP 51241393 A 19921026; US 9209016 W 19921026